177 



base. Pupation takes place on the plant itself and the adult appears 

 a fortnight later. There are two annual generations, the first ravaging 

 the crop in June to July, the second in September to October. This 

 moth probably hibernates as an imago. 



A remedial measure that is often effective is to cut off the leaves 

 level with the soil before the caterpillars penetrate to this point, the 

 operation being carried out as late as possible to avoid the danger of a 

 fresh batch of eggs being deposited on the new growth. The leaves 

 thus cut off should be burned or buried together with any useless 

 plants that may shelter the caterpillars in the neighbourhood of the 

 crop. 



PouiLLAUDE (I.). M^thodes de Lutte contre un Ravageur du Cafeier' 



k La Reunion {Cocais riridis. Green). — Bull. Soc. Sci. Med. de 



VOueM, Rennes. xxv, 8th Dec. 1916, pp. 3^-40. [Received 



6th March 1920.] 



The scale. Coccus viridis, Green, which has a wide distribution in 



the tropics, threatens the abandonment of coffee cultivation in 



Reunion. A useful natural check on it is a fungus, Ceijlialosiiorium 



■ lecanii, which under sufficiently humid conditions may destroy as 



many as 90 per cent, of the Coccids. 



Remedial measures include spraying with a resinous soap solution 

 made of 2 lb. each of resin, sodium carbonate and soap in 8 gals, 

 of water. The powdered resin and soda are boiled in a little water 

 and kept stirred. When the liquid is clear the flaked soap is added. 

 The whole is then dissolved and cooled, and the rest of the water 

 added. 



Lime-sulphur mixture (Savastano's formula) [R.A.E., A, ii, 412] 

 may also be used, or petroleum emulsion consisting of 30 lb. soft 

 . soap, 3 gals, petroleum and 100 gals, water. 



Fumigation with hydrocyanic acid gas is also recommended. 



Wesenberg-Lund (C). Insektlivet i ferske Vande. [Insect Life in 



Fresh Waters.] — Gvldendalske Boghandel, Nordisk Forlag, 



Copenhagen, 1915, 528 pp., 377 figs. Price 11.25 Kr. 



In this voluminous book the author has collected together his 



many valuable notes on aquatic insects (including Culicids and other 



Nematocera). The hterature on the subject has been consulted with 



great thoroughness and the whole forms a very valuable compendium 



of the known facts on the biology of aquatic insects up to the year 



of pubhcation (1915). 



Bergsoe (Villv.). Fra Mark og Skov. Billeder af Insekternes Liv. 



[Pictures of Insect Life from Field and Wood.] — New Edition by 



C. Wesenberg-Lund, Gvldendalske Boghandel, Nordisk Forlag, 



Copenhagen, l9lo, 2 vols., 1172 pp., 917 figs., 29pls. Price 10 Kr. 



This new and much enlarged edition of Bergsoe's old popular book 



has been issued by the editor as a pendant to the work above 



mentioned on freshwater insects. Numerous details are given, of the 



bionomics of insects noxious to agriculture and forestry as well as to 



household insects, house-flies, etc, and the work is full of excellent 



illustrations. 



